Anyone who runs a successful website knows the value of search engine optimization. it's is a wide concept in publisher’s mind that using Joomla! means getting maximum traffic from search engines because Joomla! is a very great CMS which hardly requires Search Engine Optimization (SEO). 

But, how do you SEO a CMS site such as Joomla? With Joomla Extensions! Extensions is term used to refer to any number of Joomla components, modules and plugins. Use this Extensions list if you already have a site ranked and want to see what you can implement to get your ranking higher. 

1. Using Keywords and Meta Description

@ Joomla 1.5 SEO Patch

This patch solves the issues in regards of the settings within the html head section of your html  page. The patch allows you to gain fully control over the META and title settings in the http header settings in Joomla 1.5 generated pages.

@ SC Meta - Section Category Meta Manager

With the help of this component you can easily add meta data for each of your categories and sections. This meta data shows up in the category and section views. 

2. Use a sitemap generator and generate XML sitemaps like twice a week.

@ Xmap

Xmap is a Site map generator component for Joomla, it's based on the popular Joomap component. Xmap allows you to create a map of your site using the structure of your menus. 

@ Joomap

Joomap is a sitemap component for Joomla that shows the normal Menu Structure, Content Categories, Sections and Virtuemart Categories in a hierarchical tree or a Google Sitemaps list.

@ SEF Service Map 2 (with PingBack system)

the site map can actively report (ping) new or modified items to google.com, yahoo.com and other services. Thanks to that, indexing robots (spiders) will visit your site much more often and the site can index itself without your further activity.

3. Use an Ideal Robot.txt File which do the following:

Disallow unnecessary pages, folders so search engines get to your content instead of wasting time and getting less important stuff.

Here is a sample : http://www.visionwidget.com/robots.txt

4. Proper URL and Title Structure

@ SEO Canonicalisation Plugin

SEO Canonicalisation is a system plugin for Joomla! 1.5 that enables site 'canonicalisation'.

@ Alias for Page Title Plugin

This plugin, designed to work with Joomla 1.5 will use the article alias to set the title tag.

@ HP Router

HP Router takes the URLs of the core of Joomla! and removes the IDs from the non-menu parts. 

5. Automatic Free SEO Extension for Joomla!

@ ARTIO JoomSEF

The Joomla SEO/SEF Component mainly makes your urls more search engine friendly. Instead of your urls being a mixture of numbers and letters, it allows for more understandable urls.

@ JoomSEO.

JoomSEO has a ton of different features, but most notably, it dynamically makes the content more search engine friendly.

@ AceSEF

AceSEF is a flexible and powerful SEF URLs and Meta Tags generator with an easy-to-use graphical user interface that simplifies the generation and management of your URLs.

6. Using rel=”nofollow” Attribute in outgoing or less important links.

@ Adding No Follow to Joomla Menu Links

@ insert the rel="nofollow" attribute within outgoing links 

7. On post page title of post should be written in Heading 1 (H1).

@ Add header tags to article titles

It is for this reason that you should always try to have your most important words within these tags as often as possible throughout your page.

8. Avail Joomla! ping facility to get max exposure and inbound links

@ Easy Ping

Easy Ping is a plugin that adds ping to search engines support to Joomla 1.5. It can ping popular search engines like google, yahoo, msn live, technorati, and more.

@ BlogPing

This makes it possible to ping update services whenever you create a new article in a certain section. You can specify as many update services as you like, but we recommend that you stick to about 10 services to not slow down your article creating.

9. Top 10 Joomla SEO tips for Google

Use this top ten list if you already have a site ranked and want to see what you can implement to get your ranking higher. 

Hope this helps! Maybe you have some more tips you would like to add? Feel free to write them in comments! Thanks and enjoy!